A man sexually molested a 24-year-old woman and three teen-age girls on their way to Bronx schools yesterday, police said.

The attacker first struck at 7:20 a.m. near PS 205 in the Fordham section, where he grabbed the buttocks of a 24-year-old school worker. She told cops he then jumped into a new blue Dodge minivan and sped off.

At 7:25 a.m., he came up behind a 14-year-old on her way to St. Thomas Aquinas HS, lifted her skirt and stuck his head underneath, cops said. He ran off when the girl screamed.

At 7:40 a.m. a 16-year-old girl was heading to the same school when the man exposed himself to her, police said. At 7:50 a.m., a third student was molested when the man grabbed her and kissed her buttocks, cops said.